A corporatlon



BEST AVAILABLE cop.

Nov. 23 1926. 1,608,272

P. E. GILLING v ELECTRI CAL CONDENSER Filed March 19. 1925 z INVENTOR P1955 ran/E. G/LL/MQ ATTORNEY BEST AVAILABLE COP.

; CIALTY APPARATUS COIYEEANY, 03: 39857033, Ii'r'i NEW YORK.

' ELECTRICAL Application filed March is. 1925. Serial no. 16.597.

This invention relates to electrical 'con-.

densers of the stack type, and particularly to condensers of small capacity adapted for low potential service. This type of condenser-"usuallyconsists-of a stack of sheets which usually have small superficial area and'are so small in number that the'stack is so thin as to be more or less flexible. The sheets consist usually of metal foils Karmatures) and mica sheets (dielectrics), the diameter of the mica sheets being greater than the foil sheets so as to provide insulating margins at the sices of the stack save at the sides out of which project foils of opposite polarities at spaced-apart portions of the sides.

The object of the invention is an improved means for holding the sheets in the form of a stack. said means preferably havin additional functions to be described. "The invention consists of the features illustrated in'the drawings, described herematter and pointed out in the claims.

In the past the problems involved in this type of condenser have included those -relating to the encasing or protection of the electrical stack itself comprising the armature sheets and dielectric sheets. the maintenance of a given desired capacity of such stack and the matter of cost involved in a practical solution of said features. In the present invention these objects are obtained in a practical manner and at low cost.

Of the drawings- Fig. 1 is a plan of a punched sheet metal blank which is to be bent around the condenser stack.

Fig. 2 is a plan showing the condenser stack in dotted lines, with insulating strips on its faces, and with the punching or stamping of Fig. 1 partially applied at one end of the stack, by bending along the dot and dash lines A. A of Fig. 1.

Fig. 3 is a plan like Fig. 2 but with stamping at the right-hand end fully plied to the stack, by bending along dot and dash lines B. of Fig. 1.

Fig. 4 is a plan like Figs. 2 and 3 but with two duplicate stampings C of Fig. 1 fully applied to both the right and lefthand ends of the condenser stack.

Fig. 5 is a section at 5-5 of Fig. 4.

Fig. 6 is a section at- 66 of Fig. 5.

The invention is particularly applicable the apthe to small and' low capacity condensers, 1511 though it is capable-of application to.electrical condensers of other. typesl Iii-prior condensers -ofsuch small typ--wheuein F metal clips were employed to IQttill'bthzCOIF denser sheets in .stack-rform, and. also' amdng other things to compact-orclamp' the 'stack sheets together, either the clips liave been more or less subject to disassociation-ifrom or movement relative to the stack -wor-ielse for the purpose-10f preventing such iremoval or relative movement; means have-been providcd which entered int-0.:- orextended through the stackor insulating strips at the faces thereof, for 'the purp'ose'iof holding the metal clips or clamps in permanent en gagement with the -.stack.- =Suchmeansfor securing together the-stack and its/securing means,' have been objectionable forwarious reasons among which were increased costs for labor and materials. w: The particular object of-the present-invention is an improved nieansfor permanently holding together the staek -and thezymetal securing means-or clamps. :1 According to my invention the-stackland the securing means therefor are held together without the necessity of any part extending through the stack or even entering into any part thereof or"of--the insulating strips at the stack faces. I 4

In Fig. l is shown a sheet metal 'blank which has been stamped to the shape shown by means of any suitable dies in apunching press. The metal may he brass, steel, copper, or any other suitable metal.

In Fig. 2- is shown in dotted lines a condenser stacl; having capacity determined by the number of mica sheets M and foil sheets F and F of opposite polarity. The foils F of one polality project from the left end of the stack and (when more than one foil is used) several of such foils FF are folded over on a face of the stack as shown at the left in Fig. 2. Similarly the foils F of opposite polarity project from the right-hand end of the stack and are folded over at FF 2 on a face of the stack. On the two flat faces of the stack are insulating strips 1, I (see Figs. 5 and 6) which preferably extendbeyond the mica sheets M which in turn extend (at the stack-sides from which the foils do not project) beyond the foil sheets. F F The foils F and F at the respective ends of the stack are folded over on top of one or the other of said insulating strips I, I

Insulating strips I 1", preferably consist of single strips of any suitable insulating material, but each or either of them may consist of several sheets of mica like the individual mica sheets M stacked alternately with the foil sheets F F As shown in Figs. 24, insulating sheets I, I are cut to a shape wherein their opposite sides at one end of the stack (as at the left, Fig. 2) converge from 'theend' of the stack as indicated at G. Likewise, at the right-hand end of the stack, at G (when the completed condenser is to have two metal members C as in- Figs. 4-6).

In Fig. 2 a metal stamping or punching like that shown in Fig. 1 has been bent along the two lines A, A of Fig. 1, so as to produce a U-form; and thishas been applied to the right-hand end of the stack of Fig. 2, so that one of the interior walls of the U-shaped device makes contact with the folded foils FF thereby constituting the metal U-clip aterminal of the condenser. Thus, in Fig. 2, the metal clip has been partially combined with the condenser stack- 1 In Fig- 3 the metalclip C'has been fully secured to the condenser stack, bythe bending around the sides of the stack of the four parts E- shown in Fig. 1, the bending having taken place along the four. linesB of Fig. 1. As shown in Fig. l the lines B are at an angle to the main body of the punching and generally at right. angles to lines. A, A. This angle to the main body corresponds with the angular or converging sides G of insulating strips'IfiI- of Figs. 2-4; Thus, when in Fig. 3 the bending iilong lines BB of Fi .1 has been effected, the four. parts E of 1 overlie the converging' sides of the stack, i. e. of insulating strips I I which complete the'stack'and insulate the stack as a whole from the stack terminalsf That is, the lines of bends B of Fig. 1 are parallel witlnthe converging sides G ot'i'the stack when the metalclip 'G of Fig. I is completely combined with-the stack as is shown in Fig-3:

In Fig. 4 is shown the completed 'condenser, wherein a duplicate metal clip 0 has been completely applied to the left-hand end of thestack, the blank'for such left-hand being-a duplicate of the blank shown in 1,9,. 1.3 I r The bending of the blank of Fig. 1 along the dot: and-dash-lines A and B'may be effected manually but preferably is done by means of a suitable power press. By means of such press also, when the clip C is put in place on the stack, the entire clip may be and preferablyis deformed so that it clamps the entire stack between its legs and compresses the clip into good electrical contact with the folded foils. Such clamping action holds the entire stacl-l under sufliciently high mechanical compression, especially the arlnatures F and the dielectrics M, to maintain substantially unchanging capacity of the stack. The initial bending of metal clip G into U-form may be effected prior to placing it around the end of stack S. After the deformation of the clip as a whole, and while the dies of the press are in their positions corresponding with the deformed conditions of the clip, the portions E may be bent around the sides of the stack by another operating portion of the press.

The bending operations, however, may be as follows:

First, before there is any combination of the metal clip with stack S. the blank of Fig. 1 is put in a press and the parts E are bent over at. right angles :11 ng the lines l3.

Then the resulting blank. in another operaand the entire clip deformed" into compressing relation with the stack. lVhen the condenser has two clips as shown, .both are applied and then both simultaneously deformed.v

The'deformed' U-clip or clips alone, irrespectiveof parts E', serve as the securing means for holding the micas M and foils F, F in stack form; but without some means of holding such securing means to the stack, the securing means itliable to become disassociated from the stack: and it is the parts E with the angular'or-side-converging stack construction described,- which permanently combine the clips with the stack.

In Fig. 5=are shown the foils FF projecting from the left'of the stack S and folded over on top of insulated strip P; the lefthand clip O being then applied. Likewise at the irg'ht; the foils FF of'polarity opposite the foils FF andlproj'ectin'g from theright-hand end: of staelv'S are folded over on tlieouter face of' the insulating strip and then the duplicate U-clamp applied.

In Fig. 6, which'is a view at right angles to that of Fig: 5, the completed condenser is shown, with the clipparts E bent around the sides of the stack.

It will be seen from the above that the clips C and the stack are permanently held together by means of the-construction comprising the converging sides G of the stack (Figs. 2 and 3) and the bends-B of the blank of Fig. 1 paralleling said converging sides. That the metal clips and the stack are held together in such wise as to prevent lateral movement of the clips either disas eciatin; them from the stack or permit-ting any relative movement between the clips and the stack.

As illustrated in Figs. 4-6,. the stack S is 08,272 BEST AVAILABLE com substantially enclosed by the construct-ion including the insulating strips I, I and the metal clips C including their bent-over portions E of Fig. 6, so that substantially a boxshaped structure is formed about the stack Thus the construction of the metal clips (which constitute the means for securing the condenser sheets together in the form of a stack) co-operates with the converging-side construction of the stack to hold such securing means permanently in in'nnovable relation with the stack, and this without any parts (either integral with the clips or separate therefrom but combined therewith) which either extend through the stack or enter into insulating strips I or I The coordinating angular constructions of the metal clip and the stack sides constitute this means for holding the clip and the stack permanently in co-operative relationship.

In the example shown the clips G, by deformation into compressing relation with the stack, act as stack clamps; and the metal cli s, by means of the folding over of the foils and the good electrical contact between the clips and the foils, constitute circuit terminals for the condenser, and this disclosure constitutes a preferred embodiment of the invention. But I contemplate'that tile-l1]; ventionmay be employed-inv other forms whether or not the clips serve both as clamps and circuit terminals or either of them; and the construction of the invention involving the converging stack sides and corresponding bends of the metal clipsmay bej-employcd whether or not the clips act as stack clamps or as terminals. Preferably however in all cases the clips in the invention (when in U-iorm) preferably are vdeiormedon the stack so as to act as clamps compressing the stack-sheets intosubstantially intimate contact with one another and thereby maintaining a substantially constant condenser capacity. 1 hen the construction involves two clips, the combination'permits them'to extend very close together as shown, so that when the clips-act as clamps, substantially the entire-active area of the stack-sheets. is held under compression. c 5

The clips C and insulating strips 1?, I? hold stack S, otherwise fiexiblc,. .in rigid condition.

I particularly point out and distinctly claim the part, improvement or combination which I claim as my invention or discovery, as follows:

1. In an electrical condenser of the stack type having a sheet metal stack-securing means, the means for holding the stack and securing means together which comprises a stack-construction including a stack of condenser sheets. and insulating strips on the two stack-faces, each of the opposite sides of each insulating strip having edges converging inwardly toward one another from its ends; and a; construction of the stack securing means which involves duplicate metal U-clamps at the opposite stack ends, each U-clamp having fourbends generally at right angles to the U-bend and paralleling said converging sides of the insulating strips; said duplicate U-clamps being deformed into compressing relation with the insulating strips and stack, and four portions of metal bent over at said four bends and overlying the converging sides of said insulating strips; and said U-clamps, their said bent-over portionsand said insulating strips substantially enclosing the stack of condenser sheet-s.

2. In an electrical condenser of the stack type having a metal stack-securing means, the means for holding the stack and the securing means together which comprises a stack construction wherein the opposite sides of-the-stack eachhas edges converging inwardlytoward -'one another ,from the. stack ends and wherein foils of opposite polarity projecting from oppositeiends of the stack are folded overupon ajstack face; and a construction of the sheetrmetal stack-secure ing means involving duplicate-parts at the twostack-ends, ea'ch'havinga. U-bend and four;- bends generally at right angles to. the U-bendz zand paralleling --said converging stack-ends,--said U-':bends extending over the stack ends; saidduplicate portions being ode.- formedintocompressifng relation with said folded foils lof opposite polarity respectively, therebycompacting thBStflCk -illld constituting thei U-clampsas stack-.terminals; and four portions of metal bent over-at said four bends and overlying said converging stack sides; and saidzU-berid-and bentover metal side portions :.'subs tantially-5 enclosing the ends and-'sides ofthe stack, whereby'said duplicate members substantially: enclose the elitile staks "11' 1. I :IZV' ln'an electrical'c ndenserof the stack type having 32. sheetmetal stack-securing means'gthe means for holding the stack and the securing-means together, which"-,comprises :astack construction wherein the opposite sides of the stack eachhas edges con verging inwardly toward-one another from its ends; and a constructionoiithe sheet metal stack securing device which involves duplicate parts at the two stack ends, each having a U-bend and-.also four bends gen- 'erally at right angles tothe U-bend and paralleling said convergingstack sides; said U-bend extending over and substantially; enclosing the stack ends; and portions of metal bent over at said four bends and extending in pairs over opposite converging stack sides and substantially enclosing the latter, whereby said two U-members and their bentover portions substantially enclose the entire stack.

a. In an electrical condenser of the stack type having a sheet metal stack-securing device, the means for holding the stack and securing device together which comprises a stack construction including a stack of condenser sheets, and insulating strips on the two faces of said stack, said insulating strips having oppositely converging sides; and a construction of sheet metal stack-securing device involving two bends along lines pz-rralleiing said converging): sides of the insulating strips; and portions of metal bent over at said four bends and overlying the converging sides of said insulating strips, whereby said strips and the stack-securing device co-operate in holding the securing device and stack-sheets together.

5. In an electrical condenser of the stack type having a sheet metal stack-securing device, the means for holding the stack and securing device together which comprises a stack construction'having oppositely converging sides, and stack foils of one polarity projecting from an end of the stack and folded'over on the face of the stack and a construct-ion of sheetmetal stack-securing device involving two bends lying along lines paralleling said converging stack sides: said metal stack-securing device being deformed into compressing relation into said folded foils andthe stack itself, thereby compacting the stack" and constituting the securing means a stack terminal; and portions of metal bent over at said two bends and overlying said converging stack sides.

6. In an electrical condenser of the stack type having a sheet metal stack-securing device, the means for holding the stack and securing device together which comprises a stack construction having oppositely converging sides, and stack foils of one polarity projecting from the stack end and folded over upon'a stack face; and a construction of sheet metal stack-securing device involving two bends along lines paralleling said converging stack sides, the main body of said securing device contacting with said folded foils; and portions of metal bent over at said two bends and overlying the converging stack sides.

7. In an electrical condenser of the stack type having a sheet metal stack-securing device, the means for holding the stack and securing device together which comprises a stack construction having oppositely eonverging sides; and a construction of sheet metal stacl -cecuring device which involves two bends along lines paralleling said converging stack sides; said metal stack-securing device being deformed into compressing relation with the stack, thereby compacting the same; and portions of metal bent over at said two bends and overlying the stack sides.

8. In an electrical condenser-of the stack type having a sheet metal stack-securing device, the means for holding the stack and securing device together which comprises a stack construct-ion having opposite converging sides; and a construction of sheet metal stack-securing device which involves two lines of bend into a U-form and four bends generally at right angles to the U-bends but paralleling said converging-stack sides: said U-bend enclosing a stack end of greater width between sides; and four portions of metal bent over at said four bends and extending in pairs over opposite stack sides adjacent to said'enclosed end, and substantially overlying said stacksides.

9. In an electrical condenser of the stack type having a sheet metal stack-securing device. the means {oi-holding the stack and securing device together wvhich comprises a stack construction having opposite converging sides; and a construction of sheet metal stack-securing device which involves a U- member having four bends generally at rightangles to the U bend-and paralleling saidconverging stack sides; and port-io ns of metal bent over at said-four bends and extending in pairs over opposite stack sides and substantially enclosing the same. i

10.- In an electrical condenser of-the stack type having asheet metal stack-securing de vice, the means of holding the stack and securing-means together and enclosing the stack sides which comprises astack construction having opposite converging sides; and a construction of sheet metal stack-securing device which involvesbends along lines paralleling said converging'stack sides; and metal porti'ons'bent over; at said bends and substantially enclosing the stack sides.

11. Inan lectrical condenser of the stack type having a metal stack-securing means, the means for holding the stack and the securing means together which comprises a stack construction having oppositely converging sidesj-and a construction of sheet metal stack-securing device which involves two bends along-lines paralleling said converging stack sides, the bent-over metal portions overlying the stack sides.

PRESTON E. GILLING. 

